Demo of new visual layers

Since the first series of posts in January I've been slowly working on a new set of layers that comprise a simple visual editor for Gem models. Here is a first look at the new stuff:



I talk about several layers in the demo. Here is a quick summary of them:

• FrameLayer - Manages size and position information of visual elements. Supports mapping raw coordinates to the "most appropriate" (deepest) element.
• ShapeLayer - Performs layout and drawing of the view. Can be extended to support a variety of layout and draw methods.
• SelectionLayer - Keeps track of the currently selected element. (Forgot to mention this in the demo.)
  
• MouseEventLayer - Handles raw mouse events received by the SWT canvas and forwards them to the most appropriate ShapeFacet for handling.
  
• KeyEventLayer - Handles raw key events and directs them using the current SelectionFacet.
• GraphvizLayers - Render sections of the model as "interesting" graphs using graphviz.